Question: $-\dfrac{4}{6} - \dfrac{2}{8} = {?}$
$ = - {\dfrac{4 \times 4}{6 \times 4}} - {\dfrac{2 \times 3}{8 \times 3}} $ $ = - {\dfrac{16}{24}} - {\dfrac{6}{24}} $ $ = - \dfrac{{16} - {6}}{24} $ $ = -\dfrac{22}{24}$